Yamaha Enticer 300 engine with 340 Carb rejet?

[igottajob2]

I have a working 300 engine and my 340 crankcase is leaking. Can I use a 300 motor with a 340 carb without rejetting the carb? If I do have to rejet what do I need? Also will the coil/ electrical from the 340 work on the 300 engine?